A123 has some small B-grade cells that would work great as a starting battery.
http://ecomodder.com/forum/showthrea...tml#post430806
Oil Pan used a few of these in a series/parallel pack for his diesel truck for a while. Later on he added another AMP20 pack in parallel for winter starting. I just asked him for updates on how its working out here:
http://ecomodder.com/forum/showthrea...tml#post430814